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me·so·tho·rax | \ ˌme-zə-ˈthȯr-ˌaks 
, ˌmē-, -sə- \
, ˌmē-, -sə- \Definition of mesothorax
: the middle of the three segments of the thorax of an insect — see insect illustration
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Time Traveler for mesothorax
The first known use of mesothorax was circa 1826
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